Aminocoumarin antibiotics such as Novobiocin, Coumermycin A1 and Clorobiocin act as bacterial DNA gyrase inhibitors and also possess anticancer activity by binding to the HSP90 chaperone. The 3-amino-4,7-dihydrocoumarin ring is the core moiety present in all of these antibiotics. They bind with high affinity to the GyrB subunit of the DNA gyrase enzyme. The usefulness of aminocoumarins is limited by poor water solubility and poor oral absorption, mainly due to the hydrophobic nature of these antibiotics.
Glycosyltransferase (GT) catalyses the transfer of sugar moieties from active donor molecules to specific acceptor molecules forming glycosidic bond. GTs are important tools in the synthesis of drugs. An increasing appreciation of carbohydrates as components of natural products has uncovered new opportunities in carbohydrate-based drug design. The exact identity and pattern of glycosyl moieties can influence pharmacology/pharmacokinetics, invoke biological specificity at the molecular/tissue/organism level and even define the precise mechanism of action.